Spiny Dogfish

The spiny dogfish, spurdog, mud shark, or piked dogfish, Squalus acanthias, is one of the best known of the dogfish which are members of the family Squalidae in the order Squaliformes. While these common names may apply to several species, Squalus acanthias is distinguished by having two spines (one anterior to each dorsal fin) and lacks an anal fin. It is found mostly in shallow waters and further offshore in most parts of the world, especially in temperate waters.

Once the most abundant shark species in the world, populations of Squalus acanthias have declined significantly. They are classified in the IUCN Red List of threatened species as Vulnerable globally and Critically Endangered in the Northeast Atlantic, meaning stocks around Europe have decreased by at least 95%. This is a direct result of overfishing to supply northern Europe's taste for Rock Salmon, Saumonette or Zeepaling. Despite these alarming figures, very few management or conservation measures are in place for Squalus acanthias.